1. Field of the Invention
The present invention relates to an ink container having an improved connection with a recording head, to an ink jet cartridge having such an ink container, and to an ink jet recording apparatus capable of mounting such a cartridge. More particularly, the present invention relates to an ink container having a recording head connecting portion capable of preventing ink from leaking out, an ink jet cartridge having such an ink container, and an ink jet recording apparatus that can mount such a cartridge.
2. Description of the Prior Art
Japanese Laid Open Patent Application No. 118260/1988 proposes an ink jet cartridge that consists of an ink jet recording head that ejects ink droplets hereinafter referred to simply as a recording head) and an ink container that supplies ink to the recording head, both components being integrally formed in one piece. The ink container for such an ink jet cartridge generally has installed compressed therein a porous material absorbed with ink. An ink supply port of the ink container is connected to an ink inducing port of the recording head. The ink absorbed in the porous material held in the ink container is led through a common liquid chamber of the recording head to a plurality of ink ejection nozzles, from which the ink is ejected. The ink contained in the ink container is led to the recording head by capillary action according to the amount of ink used by the recording head.
In such an ink jet cartridge, however, because an energy generating section incorporated in the recording head that produces energy for discharging ink droplets is formed integral with the ink container that supplies ink to the recording head, when ink in the ink container is run out, the recording head that is still usable has to be replaced along with the empty container. To use the recording head for as long a period as possible necessitates increasing the capacity of the ink container. These is the factor standing in the way for reducing the overall size of the ink jet cartridge.
As a means to solve this problem, Japanese Laid Open Patent Application No. 3958/1988 proposes a construction, in which the recording head and the ink container can be connected to and disconnected from each other on a carriage of the ink jet recording apparatus (hereinafter referred to simply as a recording apparatus). This on-carriage head-container separation type allows the full use of the recording head to the end of its life by repeatedly exchanging only the ink container, making it possible for a single recording head to print a large number of characters.
As such a separation type of the ink container, there is a known container having an open-close valve mechanism which is capable to close a connecting opening in order to prevent ink from outflow toward the outside of the container, the outflow being occurred from the inside thereof through a connecting portion.
With this conventional construction, when the ink container, after having been coupled to the recording head on the carriage, is disconnected again from the recording head in order to perform the exchange of ink container on the basis of the data which informs empty of the container, the outflow of ink from the inside of the ink container is controlled by the valve mechanism. However, there is a problem that some ink, in whatever amount, remains in the vicinity of the outer peripheral part of the connecting portion of the ink container, the connecting portion being connected with the recording head. If the amount of the ink remained in the connecting portion is large, the ink may spill from the connecting portion of the ink container into the recording apparatus. After the ink container is removed from the carriage, ink may be leaked out from the ink container to fall fouling the surrounding of the recording apparatus.